U.S. patent application number 11/856985 was filed with the patent office on 2008-05-22 for production of lower molecular weight hydrocarbons.
Invention is credited to Jeffrey P. Newton.
Application Number | 20080116111 11/856985 |
Document ID | / |
Family ID | 39200831 |
Filed Date | 2008-05-22 |
United States Patent
Application |
20080116111 |
Kind Code |
A1 |
Newton; Jeffrey P. |
May 22, 2008 |
PRODUCTION OF LOWER MOLECULAR WEIGHT HYDROCARBONS
Abstract
The present invention relates generally to processes for
upgrading (cracking and hydrogenation) of high molecular weight
hydrocarbons using a catalytic composition at moderate
temperatures, methods for stabilizing the upgraded product, and
methods for reducing carbon oxides using a catalytic
composition.
Inventors: |
Newton; Jeffrey P.; (Ithaca,
NY) |
Correspondence
Address: |
DARBY & DARBY P.C.
P.O. BOX 770, Church Street Station
New York
NY
10008-0770
US
|
Family ID: |
39200831 |
Appl. No.: |
11/856985 |
Filed: |
September 18, 2007 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
60826035 |
Sep 18, 2006 |
|
|
|
Current U.S.
Class: |
208/111.1 ;
208/107 |
Current CPC
Class: |
C10G 47/12 20130101;
C10G 47/02 20130101 |
Class at
Publication: |
208/111.1 ;
208/107 |
International
Class: |
C10G 47/04 20060101
C10G047/04; C10G 47/00 20060101 C10G047/00 |
Claims
1. A method of cracking a high molecular weight hydrocarbon to form
a lower molecular weight hydrocarbon product, comprising: (I)
admixing (a) a high molecular weight hydrocarbon having an API
value of less than about 12 and (b) an aqueous catalytic
composition prepared by admixing and reacting, in an aqueous
solution, a transition metal salt and particles of silicon dioxide,
aluminum oxide, ferric oxide, calcium oxide, and titania or boron
oxide; (II) reacting the admixture from step (I) at a temperature
from about 50.degree. C. to about 200.degree. C., thereby
hydrogenating and cracking the high molecular weight hydrocarbon to
form a lower molecular weight hydrocarbon product; said lower
molecular weight product having an API value greater than the API
value of the high molecular weight hydrocarbon composition.
2. The method of claim 1, wherein the aqueous catalytic composition
is prepared by admixing and reacting, in an aqueous solution i.
about 15 to 40 weight percent cement, ii. about 55 to 80 weight
percent volcanic ash, iii. about 2 to 8 weight percent titanium
dioxide or boron oxide, and iv. about 3 to 10 weight percent
transition metal salt, the weight percents being based on the total
weight of components (i)-(iv).
3. The method of claim 2, wherein the volcanic ash component is one
or more components selected from scoria, basalt, pyroclastic rock,
tuff, tuffstone, volcanic glass, pumice, mafic rock, ultramafic
rock, and silicate-based zeolites.
4. The method of claim 1, wherein step (I) comprises admixing (a) a
high molecular weight hydrocarbon having an API value of less than
about 12, (b) carbon dioxide, and (c) an aqueous catalytic
composition prepared by admixing and reacting, in an aqueous
solution, a transition metal salt and particles of silicon dioxide,
aluminum oxide, ferric oxide, calcium oxide, and titania or boron
oxide.
5. The method of claim 1, further comprising (III) stabilizing the
lower molecular weight hydrocarbon product by admixing it with a
diluent comprising a saturated hydrocarbon having from 5 to 25
carbon atoms.
6. The method of claim 4, further comprising (III) stabilizing the
lower molecular weight hydrocarbon product by admixing it with a
diluent comprising a saturated hydrocarbon having from 5 to 25
carbon atoms.
7. The method of claim 1, further comprising: (III) recovering the
lower molecular weight hydrocarbon from the product of step (II);
and (IV) admixing said lower molecular weight hydrocarbon from step
(III) with a second aqueous catalytic composition thereby forming a
hydrocarbon product having a molecular weight still lower than said
lower molecular weight hydrocarbon product, wherein the second
aqueous catalytic compositions is prepared by admixing and
reacting, in an aqueous solution, a transition metal salt and
particles of silicon dioxide, aluminum oxide, ferric oxide, calcium
oxide, and titania or boron oxide.
8. The method of claim 1, wherein the high molecular weight
hydrocarbon is formed by diluting bitumens, asphaltenes, heavy
oils, or tars.
9. The method of claim 7, wherein the high molecular weight
hydrocarbon is formed by diluting the bitumens, asphaltenes, heavy
oils, or tars with a C.sub.5 to C.sub.25 alkane or cycloalkane.
10. The method of claim 1, wherein the high molecular weight
hydrocarbon is admixed with the aqueous catalytic composition at a
weight ratio of from 2:1 to 4:1.
11. The method of claim 1, wherein the transition metal salt is
ferrous chloride.
12. The method of claim 10, wherein the aqueous catalytic
composition is formed from the following components: i. about 25 to
50 weight percent silicon dioxide, ii. about 6 to 20 weight percent
aluminum oxide, iii. about 5 to 15 weight percent ferric oxide, iv.
about 15 to 30 weight percent calcium oxide, v. about 2 to 10
weight percent titania or boron oxide, and vi. about 2 to 10 weight
percent ferrous chloride, the weight percents being based on the
total weight of components (i)-(vi).
13. The method of claim 1, wherein the aqueous catalytic
composition is formed from the following components: i. about 15 to
40 weight percent cement, ii. about 55 to 80 weight percent
volcanic ash, iii. about 2 to 8 weight percent titanium dioxide or
boron oxide, and iv. about 3 to 10 weight percent transition metal
salt, the weight percents being based on the total weight of
components (i)-(iv).
14. A method of forming and stabilizing a lower molecular weight
hydrocarbon prepared from the cracking and hydrogenating of a high
molecular weight hydrocarbon, comprising: admixing (a) a high
molecular weight hydrocarbon having an API value of less than about
12, (b) carbon dioxide, and (c) an aqueous catalytic composition,
said aqueous catalytic composition having been prepared by admixing
and reacting, in an aqueous solution, a transition metal salt and
particles of silicon dioxide, aluminum oxide, ferric oxide; calcium
oxide, and titania or boron oxide, thereby forming a stabilized
lower molecular weight hydrocarbon product.
15. The method of claim 13, wherein the amount of carbon dioxide
relative to the 1 bbl. of the high molecular weight hydrocarbon is
from 5 to 50 scft.
16. The method of claim 13, further comprising admixing with the
lower molecular lower molecular weight hydrocarbon a diluent
comprising a saturated hydrocarbon having from 5 to 25 carbon
atoms.
17. A method of reducing the concentration of carbon oxides in a
gaseous or liquid medium comprising: passing said medium into an
aqueous catalytic composition or an admixture of the aqueous
catalytic composition and optionally a liquid hydrocarbon, at a
temperature of at least 50.degree. C. and pressure sufficient to
react the carbon oxides; said aqueous catalytic composition being
prepared by admixing and reacting, in an aqueous solution, a
transition metal salt and particles of silicon dioxide, aluminum
oxide, ferric oxide, calcium oxide, and titania or boron oxide.
18. A method of forming a lower molecular weight hydrocarbon from a
high molecular weight hydrocarbon, comprising: (a) admixing a high
molecular weight hydrocarbon having an API value of less than about
12 and a first aqueous catalytic composition thereby forming a
lower molecular weight hydrocarbon product; (b) recovering the
lower molecular weight hydrocarbon from the product of step (a);
and (c) admixing said lower molecular weight hydrocarbon from step
(b) with a second aqueous catalytic composition thereby forming a
hydrocarbon product having a molecular weight still lower than said
lower molecular weight hydrocarbon product, wherein each of the
first and second aqueous catalytic compositions is prepared by
admixing and reacting, in an aqueous solution, a transition metal
salt and particles of silicon dioxide, aluminum oxide, ferric
oxide, calcium oxide, and titania or boron oxide, and the first and
second aqueous catalytic compositions are the same or different.
Description
PRIORITY DATA
[0001] This application claims priority of U.S. Provisional
Application No. 60/826,035, filed Sep. 18, 2006, which is
incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The present invention relates generally to processes for
upgrading (cracking and hydrogenation) of high molecular weight
hydrocarbons using a catalytic composition at moderate
temperatures, methods for stabilizing the upgraded product, and
methods for reducing carbon oxides using a catalytic
composition.
BACKGROUND OF THE INVENTION
[0003] The upgrading of viscous high molecular weight hydrocarbons
to form lower viscosity, lighter weight molecular hydrocarbon
mixtures has long been studied. Traditionally, this involved the
cracking and hydrogenating of the hydrocarbon molecules that
make-up the high molecular weight viscous material at extremely
high temperature and pressure. To improve the efficiency of this
process, the inventor of the subject application developed a
process for upgrading these viscous materials under substantially
less rigorous conditions. The process involves contacting an
aqueous catalytic composition with high molecular weight
hydrocarbons to produce a lower molecular weight hydrocarbon
product, and recovering the lower molecular weight hydrocarbon
product. The catalytic composition comprises cement (preferably
Portland cement), a volcanic ash component, titanium dioxide, and a
transition metal salt. This work and publications related to
upgrading and to other aspects of the invention is described in
U.S. Publication No. 2004/0016676 A1 published on Jan. 29, 2004,
the disclosure of which is incorporated by reference herein. While
the invention set forth in such publication represents a major
economic and technical breakthrough, in certain instances drawbacks
have become evident.
[0004] More particularly, it has been discovered that the specific
catalyst composition described does not consistently give optimum
results for all forms of heavy oil and bitumen structures and
further that the viscosity and density of the product produced is
not uniformly stable over an extended period.
SUMMARY OF THE INVENTION
[0005] It has now been discovered that markedly improved viscosity
reduction and improvement in product composition can be achieved in
the upgrading process described in U.S. Patent Publication No.
2004/0016676 by modifying the catalytic composition and the process
conditions used in the upgrading process. With respect to the
catalytic composition precursors, increased amounts of the volcanic
ash component and decreased amounts of cement are used. The
temperature used in the upgrading process is preferably from about
50.degree. C. to about 200.degree. C. and more preferably from
about 75.degree. C. to about 110.degree. C., in contrast with the
ambient temperatures used in the Examples of applicant's prior
publication.
[0006] It has further been found that the product of the process of
the invention can be further improved by subjecting the product of
a first treatment with the aqueous catalytic composition to
additional treatments, with or without the addition of a diluent
(e.g., a hydrocarbon based solvent), to further upgrade the
product. This technique may be done under the same or less rigorous
conditions as the first treatment and is of particular value with
certain high molecular weight hydrocarbon feed stocks, such as
heavy oil and bitumen.
[0007] Another embodiment of the invention is the discovery of
techniques that stabilize, i.e., hold substantially constant the
viscosity and/or density, of the upgraded product. These techniques
include adding a diluting hydrocarbon to the product of the
upgrading reaction. Preferably, the diluent is added in an amount
ranging from about 5 to about 15% by weight based upon 100% total
weight of the lower molecular weight hydrocarbon. These stabilizing
techniques are useful in all types of oils but are particularly
useful in heavy oils and bitumen that have higher polar (resin),
aromatic, and asphaltene contents. The amount of diluent added can
be selected to achieve a desired concentration of low molecular
weight hydrocarbon product suitable for the intended transportation
method (e.g., pipeline transport or trucking specification).
[0008] A still further finding is that the presence and/or the
addition of carbon dioxide (CO.sub.2) to the process produces
reaction products greatly reduced in carbon oxides, enhances
viscosity and density reduction, and stabilizes the product (e.g.,
stabilizes the density and/or viscosity of the product). Heavy oil
frequently contains entrained carbon dioxide from the oil formation
or from injection of carbon dioxide into the well to increase
production. The heavy oil used in the tests discussed below
contained up to about 5% entrained carbon dioxide. By converting
the entrained carbon dioxide into useful hydrocarbon products, the
inventive method creates valuable hydrocarbon products from carbon
dioxide that is a disposal and environmental liability
otherwise.
[0009] The inventive method can also convert carbon oxides from
other sources (such as the burners used to heat the oil-in-water
emulsion for the upgrading process of the present invention, as
well as exhausts from coal burning furnaces, Fischer-Tropsch
systems for the generation of hydrogen (H.sub.2), and natural gas
burning) into useful organic compounds without inhibiting the
upgrading process. When carbon oxides are added to the process or
are inherently present in the high molecular weight hydrocarbon
feedstock, the organic compounds (e.g., hydrocarbons and alcohols)
generated by the conversion reaction enhance the upgrading process
by acting as an additional diluent to increase the API value of the
lower molecular weight hydrocarbon product.
[0010] Additionally, it has been discovered that the catalytic
composition, such as described herein and in the inventor's prior
publication, can, in an aqueous mixture or emulsion, convert carbon
oxides, most specifically carbon dioxide, to organic compounds free
or substantially free of such carbon oxides. This conversion
process can be performed in the presence or absence of hydrocarbons
(such as high molecular weight hydrocarbons and lower molecular
weight hydrocarbons). The aqueous catalytic composition can be
prepared, for example, by admixing and reacting, in an aqueous
solution, a transition metal salt and particles of silicon dioxide,
aluminum oxide, ferric oxide, calcium oxide, and titania or boron
oxide.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 depicts an overview of one illustrative embodiment of
the inventive method for upgrading high molecular weight
hydrocarbons and converting carbon oxides to light
hydrocarbons.
[0012] FIGS. 2-5 are scanning electron microscope photographs of
the particles suspended in the aqueous catalytic composition.
DETAILED DESCRIPTION OF THE INVENTION
[0013] The upgrading process of the invention is carried out at
relatively moderate temperature (preferably less than about
200.degree. C. and more preferably less than about 150.degree. C.)
in the presence of an aqueous catalytic composition. The pressure
utilized is generally ambient or subject to whatever pressure may
build up from the pumping of fluids and other inherent process
steps. External pressurization is generally not required. However,
when desired, external pressurization may be achieved by
introducing an external pressuring gas, such as carbon dioxide
and/or a hydrocarbon gas. According to one embodiment, the process
is performed at approximately three atmospheres to maintain the
flow of the emulsion. The process is applicable to both surface
upgrading of heavy oils and bitumen and subsurface enhanced
recovery applications of heavy oil and bitumen. Optionally, this
process can be adapted to convert carbon oxides, such as carbon
dioxide and carbon monoxide, to light hydrocarbons, alcohols,
and/or other organic compounds. The carbon oxide conversion can
actually enhance the upgrading function by providing additional
diluent low molecular weight hydrocarbons and/or alcohols to
increase the API value of the high molecular weight hydrocarbons
and providing stability to the upgraded product.
[0014] This inventive cracking and hydrogenation process, though
operating at higher temperatures than Applicant's prior work, still
operates at a more moderate temperature and pressure than the
conventional cracking and hydrogenation processes. Furthermore, in
contrast to the conventional cracking and hydrogenation processes
little or no residual carbon dioxide or carbon monoxide is released
into the atmosphere, because the inventive process converts these
oxides.
[0015] Surprisingly, the aqueous catalytic composition performs the
cracking and hydrogenation without any substantial "gumming" or
coating of the surfaces of the aqueous catalytic particles in the
oil-in-water emulsion. The advantage of substantial coking permits
the process to operate continuously. Also the process results in
complete or partial desulfurization by reduction of the
sulfur-containing species. Sulfur species pose a significant
problem in the oilfield industry, because many feed stocks, such as
tar, tar sands, heavy crude, shale oil, and bitumens, contain high
sulfur levels that cause pollution, corrosion and undesired results
in the refining process (e.g., with refinery catalysts).
[0016] The process of the present invention can convert high
molecular weight hydrocarbons having an API value of from 8 to 12
(and generally a viscosity higher than 350 cS at about 7.degree.
C.) to lighter molecular weight hydrocarbons having an API value of
greater than 23 (for example, from 23 to 33).
[0017] If the resulting admixture of the high molecular weight
hydrocarbon and aqueous catalytic composition does not have a
significant percentage of carbon oxides, additional carbon oxides
may be added until the admixture contains between 2 and 5 weight
percent (or more) carbon oxide. Typically, greater than 25% of the
total carbon oxide is converted to light hydrocarbons.
[0018] The carbon oxides may be converted to light hydrocarbons
and/or other organic compounds, e.g., low molecular weight alcohols
(methanol, ethanol and n- and iso-propanol) by adding the carbon
oxides to an aqueous catalytic composition or an admixture of the
aqueous catalytic composition and a liquid hydrocarbon. The carbon
oxides are added under conditions of temperature and pressure
sufficient to convert them to the organic compounds. The aqueous
catalytic composition for this conversion is prepared by admixing
and reacting a transition metal salt and particles of silicon
dioxide, aluminum oxide, ferric oxide, calcium oxide, and titania
or boron oxide in an aqueous solution. For maximum effectiveness,
the particles should have a Blaine grain fineness of at least
3000.
[0019] Additionally, the inventive catalyst can be used for the
conversion of coal to liquid hydrocarbons using processing
temperatures 25.degree. to 50.degree. C. higher than those
described above for the liquid hydrocarbons. The coal is first
crushed to facilitate its suspension in the aqueous system prior to
being fed thereto. Coal is a very complex hydrocarbon with a very
low hydrogen to carbon ratio compared to other liquid and
semi-liquid hydrocarbons. The process for converting coal to liquid
hydrocarbons is essentially the same as for the high molecular
weight hydrocarbons described above, however, coal requires more
energy due to the complex hydrocarbon bonds and the low hydrogen to
carbon ratio. However, even with coal's greater energy
requirements, this process is a very economical method of producing
hydrocarbons from coal without producing a carbon oxide gas
intermediate.
[0020] The inventive process may also be used in down-hole or
subsurface enhanced recovery applications (e.g., for oil and
bitumen). Applications of the process can be considered in steam or
heat driven systems and in combination with carbon dioxide
injection in unconsolidated reservoirs at depths of less than 1000
meters.
[0021] Furthermore, there should be no negative environmental
consequences to the disposal of the used aqueous catalytic
composition when it is not reusable. According to current
laboratory data, virtually all of the carbon atoms introduced into
the process employing the inventive method to upgrade high
molecular weight hydrocarbons remain in the upgraded hydrocarbon
output stream. This includes any carbon atoms introduced from the
high molecular weight hydrocarbon, any added or formed diluent
hydrocarbon, and any additional carbon added from streams such as
carbon dioxide or carbon monoxide streams. Upgrading is
accomplished by hydrogen addition, not carbon elimination.
[0022] The inventive process has a low requirement for natural gas
to provide system heating. The maximum temperature needed is less
than about 200.degree. C..+-.20.degree. C. and preferably less than
about 110.degree. C..+-.20.degree. C. If the system is being
applied to an oil-water emulsion that is naturally hot, above
75.degree. C., then the intrinsic heat in the incoming emulsion is
all that is required for the process to work efficiently.
[0023] There is no requirement for the addition of methane or other
hydrocarbons as a source of hydrogen for the cracking and
hydrogenation. The produced water and/or fresh water (whichever is
available) in the emulsion provides the source of hydrogen.
[0024] Two to three times more, by weight, of light hydrocarbon
compounds are contained in the treated (or upgraded) oil than in
the untreated oil, with the same amount of diluent hydrocarbon
having been added to each. This has a significant positive impact
on the value of the treated crude oil.
[0025] There are significant reductions in the aromatic and polar
(resin) fractions of the upgraded oil, with concurrent and
significant increases in saturated and paraffins fractions. The
bromine number measured during the pilot test was reduced from 3.0
in the untreated oil to 2.2 in the treated oil. The 15.degree. C.
pour point of the untreated oil was reduced to -51.degree. C. in
the treated oil. This indicates a great degree of positive chemical
change.
[0026] For hydrocarbons having a boiling point above 260.degree.
C., using the SAPA analysis as a basis, there are typically
significant reductions in the aromatic, polar (resin), asphaltene,
and saturate fractions of the upgraded oil, with concurrent and
significant increases in saturates or paraffin fraction. There is
also typically a decrease in the aromatic fraction in the boiling
point temperature range of 0.degree. C. to 260.degree. C. using the
PNA analysis as a basis. The bromine number measured during the
various pilot tests to date has been always reduced, which is an
indication of a reduction of unsaturated bonds. The pour point of
the untreated oil is significantly reduced in the treated or
upgraded oil compared to the untreated oil. These test results
indicate a great degree of positive chemical change.
Catalytic Composition
[0027] The catalytic composition used in practicing the invention
is an aqueous admixture formed by reaction in water certain
inorganic components referred to herein as "precursors" or
"precursor components." This admixture of active catalytic
components in water is generally referred to herein as the "aqueous
catalytic composition." The admixture can be a slurry or
suspension.
[0028] Generally, the precursor components for forming the
catalytic composition include SiO.sub.2, Al.sub.2O.sub.3,
Fe.sub.2O.sub.3, CaO, a transition metal salt, and titanium or
boron oxide. Typical ranges of the precursors are shown in Table 1
below. All weight percents are based on the total weight of these
active components when combined.
TABLE-US-00001 TABLE 1 Particulate Broad Range Preferred Component
(wt. %) Range (wt. %) SiO.sub.2 10-60 25-50 Al.sub.2O.sub.3 2-20
6-20 Fe.sub.2O.sub.3 2-25 5-15 CaO 10-50 15-30
TiO.sub.2/B.sub.2O.sub.3 3-10 2-8 Trans. Metal Salt 3-20 3-10
Minor amounts of other compounds, such as magnesium and sodium
oxide and calcium sulfate, may also be present without any
deleterious effect.
[0029] An economical alternative to utilizing the compounds above
in their pure form is to prepare the catalytic composition from
composite materials to provide some or all of the components. For
example, a cement and volcanic ash can provide the SiO.sub.2,
Al.sub.2O.sub.3, Fe.sub.2O.sub.3, and CaO precursor components.
Table 2 below illustrates the broad and preferred ranges of
compositions using, in part, composites.
TABLE-US-00002 TABLE 2 Particulate Broad Range Preferred Component
(wt. %) Range wt. % Cement 10-45 15-40 Component Volcanic Ash
>50-85 55-80 TiO.sub.2 3-10 2-8 Transition 3-20 3-10 Metal
Salt
[0030] The precursor components of the catalytic composition and
the amounts thereof can be varied depending on the specific high
molecular weight hydrocarbon feedstock being treated, whether
significant conversion of carbon oxides is to take place, whether
coal is being converted to liquid hydrocarbons, and the like.
Optimization for each can be readily determined by simple
experimentation. The starting materials are added to the water,
i.e., SiO.sub.2, Al.sub.2O.sub.3, Fe.sub.2O.sub.3, CaO, a
transition metal salt, titanium or boron oxide, a volcanic ash
component, and a cement component. Sufficient water is added so
that the dry weight of the precursor components in the aqueous
catalytic composition is from about 4 to about 35 weight
percent.
[0031] To form the catalytic composition, all of the active
components must either be in an aqueous solution or in a
particulate form. If in particulate form, the particles should
preferably have a Blaine grain fineness of 3000 or more. Blaine
grain fineness is a ratio of a particle's surface area (in square
centimeters) to weight (in grams).
[0032] The cement component is preferably a Portland cement.
Portland cements are mixtures of limestone and clay that have been
ground and treated in a kiln from 1400 to 1600.degree. C. About 24
wt. % of Portland cement by weight is calcium silicate and about 66
wt. % is CaO. Impurities can include up to about 3 wt. % of
alumina, ferric oxide, and magnesia.
[0033] The volcanic ash component can be one or more of the
following materials: scoria, pumice, tuff, e.g., tuffstone, mafic
volcanic rock, e.g., ultramafic volcanic rock, pyroclastic rock,
volcanic glasses, basalt or silica-based zeolites. Scoria is the
most preferred. Scoria is the most common material in volcanic
cones and is formed of small particles (about 1 cm across) of
hardened volcanic lava. Scoria from the Washington/Oregon border is
most preferred. It contains about 55% SiO.sub.2 and about 12%
Fe.sub.2O.sub.3.
[0034] British Columbia scoria consists of about 46% SiO.sub.2,
about 18% Fe.sub.2O.sub.3, about 8% CaO, and about 2.4% TiO.sub.2.
Scoria from southern Mexico consists of about 79% SiO.sub.2 and
about 6.6% Fe.sub.2O.sub.3. Mafic rock is defined as igneous rock
which contains substantial quantities of silicates, such as
pyroxene, amphibole, olivine, and mica. Ultramafic rock is a
volcanic rock with an ultrabasic composition and over 90% composed
of FeMg minerals, predominantly olivine, orthopyroxene, and
clinopyroxene. Volcanic glasses are called obsidian and consist of
silica particles fused by the intense heat of a volcano. Basalt is
a mafic, igneous rock composed of plagioclase. Different varieties
of basalt differ in their degree of silica saturation. Zeolites are
a family of aluminum silicate minerals that can occur naturally or
be produced synthetically. Zeolites from British Columbia typically
consist of about 89% SiO.sub.2, 0.8% Fe.sub.2O.sub.3, and about 1%
CaO.
[0035] Any transition metal salt with a +2 or +3 oxidation state
can be used as a precursor component of the catalytic composition.
Preferred compounds include ferric chloride, ferrous chloride, and
cobalt chloride. Ferrous chloride is the most preferred. The
transition metal salt can be utilized in particulate or aqueous
form. If used in aqueous form, only the weight attributable to the
active component (the transition metal salt) should be considered
in determining weight percents of the active components.
[0036] The titania useful as a component of the precursor
composition exists naturally in four different forms: rutile
(tetragonal), anatase (octahedrite), brookite (orthorhombic), and
titanium dioxide (B) (monoclinic). While any of these forms of
titania can be utilized with the present invention, the most
preferred is the anatase form. Boron oxide (B.sub.2O.sub.3) can
also be substituted and used in place of and in combination with
TiO.sub.2.
[0037] The terms "high molecular weight hydrocarbon" and "low
molecular weight hydrocarbon," as used herein, are terms relative
to one another. The former term signifies a mixture of
hydrocarbons, with or without their entrained impurities, with an
average molecular weight of the hydrocarbons significantly higher
than the average molecular weight of the hydrocarbons in a lower
molecular weight hydrocarbon. Thus, the use of the terms "high
molecular weight hydrocarbon" and "low molecular weight
hydrocarbon" does not signify any particular molecular weight
ranges.
[0038] High molecular weight hydrocarbons are typically materials,
such as crude oils, asphaltenes, tars, and heavy oils, which have
limited or no practical use, but which can be converted to more
valuable and useful lower molecular weight hydrocarbons via
chemical means. Medium oils generally have resins or polar
fractions less than about 25% of the weight of the total oil and
have an API gravity of 22.3 to 32 with viscosities in the range of
about 100 to 1000 centipoise; heavy oils generally have resins or
polar fractions between about 25 and 40% of the total weight of the
oil and have an API gravity of generally above 10 but less than
22.3 with viscosities greater than about 1000 centipoise; tars
generally have resins or polar fractions greater than about 40% of
the total weight of the oil and have an API gravity less than about
8 to 10 and a viscosity greater than about 8000 centipoise.
[0039] The lowest molecular weight hydrocarbons can include C.sub.1
to C.sub.4 gases, e.g., methane, propane, and natural gas. When
these gases are present as part of the lower molecular weight
hydrocarbon product, they impart an even higher API value.
[0040] The overall quality of the upgraded hydrocarbons is also
improved as demonstrated by Saturates, Aromatics, Polars, and
Asphaltenes (SAPA) and Paraffins, Naphthenes, and Aromatics (PNA)
tests. These hydrocarbons and substrates can be treated on the
earth's surface or in subsurface deposits at more moderate
temperatures and pressures than conventional cracking and
hydrogenation technologies.
[0041] In the case of highly viscous fuels, it may be advantageous
to dilute the high molecular weight hydrocarbon with a lower
molecular weight diluent hydrocarbon. The diluent can be a
hydrocarbon such as refined and unrefined alkanes and cycloalkanes
in the C.sub.5 to C.sub.25 range. Examples of readily available
diluents include diesel fuel, naphtha, and diluent hydrocarbons
from other refining processes which are rich in hydrocarbons in the
C.sub.5 to C.sub.25 range. Condensate is a common example of an
acceptable diluent hydrocarbon from other refining processes. Any
hydrocarbon liquids with a boiling point below about 200.degree. C.
are also suitable. The composition of the diluent is not critical
because it is primarily to reduce the viscosity of the heavy high
molecular weight hydrocarbon feedstock to facilitate mixing with
the aqueous catalytic combination. Of course, the diluent must not
interfere with subsequent refining of the upgraded hydrocarbons.
Even if the diluent is not substantially saturated it can be used,
because the catalytic reaction can hydrogenate the non-saturated
hydrocarbons. However, this can decrease the efficiency of the
primary cracking and hydrogenation reactions.
[0042] Another method of enhancing the contact between the reactive
particles in the aqueous catalytic composition and the high
molecular weight hydrocarbon feedstock is to heat the latter to a
moderate temperature such that it flows more freely. The amount of
heat that can be added is constrained by the need to optimize the
temperature of the reaction and economic considerations. Another
consideration is the viscosity and thickness of the high molecular
weight hydrocarbon to be treated; thicker, more viscous
hydrocarbons require more heat than less viscous hydrocarbons. Of
course, these two methods can be utilized together to achieve
optimum results.
Preparation of the Catalytic Composition
[0043] The aqueous catalytic composition used in the experiments
discussed below was made by the following method: An aqueous
solution of about 33% (by weight) aqueous ferrous chloride solution
was first mixed with the desired amount of water and, thereafter
suitable amounts of particles of the other precursor components
were added. The mixture was then thoroughly mixed to form the
aqueous catalytic composition. Preferably, the resulting mixture
contains about 15 weight percent of the precursors.
Composition of the Catalyst
[0044] The aqueous catalytic composition is significantly different
than its precursor components. Several reactions occur within the
aqueous mixture to form some known and some novel reactive
colloidal minerals and compounds. The scanning electron microscope
(SEM) images of the reactive particles found after the reaction
characterize these particles. New crystal forms do not match any
known crystalline structure. Specifically, the x-ray diffraction
(XRD) spectrums of the crystalline structures were compared to
known compounds having comparable empirical formulas. Based on the
SEM images and XRD spectra, at least CaCO.sub.3 has formed new
crystalline structures that do not match any known crystal
structure.
[0045] The catalytic particles in the aqueous catalytic composition
are mineral assemblages composed of silicate minerals and metal
oxides. They have highly irregular, amorphous surface layers of
transition metal oxides with micro-silicate mineral inclusions.
[0046] FIGS. 2 to 5 are SEM images of various reactive surfaces of
the particles. These amorphous surfaces have various submicron
sized cavities and indentations. Without being bound by any
particular theory, applicant believes that these cavities and
indentations are the active locations that facilitate the cracking
and hydrogenation reactions.
The Upgrading of the Heavy Hydrocarbons
[0047] To initiate the cracking and hydrogenation reactions, the
aqueous catalytic composition is brought into intimate contact with
the high molecular weight hydrocarbon feedstock. The laboratory and
pilot scale tests have demonstrated that optimal yield can be
obtained by carefully adjusting the amount of the diluent
hydrocarbon and the temperature of the mixing process. This is
evidenced by the Saturates, Aromatics, Polars, and Asphaltines
(SAPA) test and the Paraffins, Naphthalenes, and Aromatics (PNA)
test. The water/heavy-oil or bitumen emulsion is preferably
contacted with the aqueous catalytic composition at a temperature
range of 50.degree. C. to 200.degree. C., and preferably 65.degree.
C. to 110.degree. C. The cracking and hydrogenation reactions
produce a chemically much-improved and a lighter crude oil product.
The volume of diluent hydrocarbon added is preferably 40% to 50%
less than what is normally required to reduce the viscosity to the
typically required pipeline value of 280 cs at 7.degree. C. In the
pilot tests described below, it was found there was a 200% to 300%
increase in the concentration of the 0.degree. C. to 200.degree. C.
boiling point hydrocarbons after treatment as compared with the
control of the comparably diluted untreated high molecular weight
hydrocarbons.
[0048] In performing the inventive process, the aqueous catalytic
composition to high molecular weight hydrocarbon loading can vary
from a ratio of 2:1 to 4:1. The preferable loading ratio is about
3:1. This loading varies depending on the high molecular weight
hydrocarbon being processed and the desired lower molecular weight
hydrocarbon products. Simple experimentation can be performed to
determine the optimal loading for a given set of high molecular
weight hydrocarbon and desired products.
[0049] Where carbon oxides, e.g., CO.sub.2, is added to the feed,
based on processing 300 barrels (bbls) per 24 hour day of the high
molecular weight hydrocarbon feed, at least one standard cubic foot
per minute (scfm) of the carbon oxide is added. Preferable amounts
of 6 to 10 scfm or more may be added. Based on 1 bbl. of the high
molecular weight hydrocarbon, broadly from 5 to 50 scft of carbon
diooxide may be used.
[0050] In the examples described below, 3.5 to 7 scft/min of
CO.sub.2 was feed to the 300 bbl/day of oil or 0.21 bbls/min to
each of heavy barrel of oil. The rate of catalyst addition was such
that each barrel of oil contained from 1.8 to 2.3 wt. % of the
catalyst (based on the dry weight of precursors). Since a barrel of
pure heavy oil weighs 350 pounds, there are 6.3 to 8.05 pounds of
catalyst used per barrel or 1.32 to 1.69 pounds of catalyst for
0.21 barrels of oil. Accordingly, 3.5 to 7 scft of CO.sub.2 and
1.32 to 1.69 pounds of dry precursors were used for each 0.21
barrels of oil. Additionally, 0.63 barrels of water were also used
in one minute.
[0051] Proportionate amounts of CO.sub.2 would be useful for
processing greater of lesser amounts of oil. The optimum amount can
be readily determined recognizing that the object is to avoid the
substantial amounts of carbon oxides in the low molecular
hydrocarbons and/or in the gaseous by-products. Use of lower
amounts can be used, and such amounts shall, of course, be
converted, thus achieving benefits of the invention. Excessive
amounts will likely not be completely converted to organic products
resulting in the presence of substantial amounts of the carbon
dioxide in the low molecular hydrocarbons and/or in the gaseous
by-products. The carbon oxides can be added as a gaseous or liquid
feed. While the feed can be of a high purity, feeds having at least
five percent or less of carbon oxides can be treated. Generally,
75% conversions of the carbon oxides can be obtained, though the
process would be of great value with considerably lower
conversions. In the absence of oil, the conversions are somewhat
lower, say in the order of 50%.
[0052] FIG. 1 represents the semi-batch apparatus used for the
pilot scale experiments discussed below to upgrade high molecular
weight hydrocarbons and revert carbon oxides. The high molecular
weight hydrocarbons are fed via line 112, pump 115, and line 117 to
heat exchanger 140. Concurrently, water is fed from tank 120
through line 122, pump 125, and line 127 and diluent hydrocarbon is
fed from tank 130 via line 132, pump 135 and line 137 to heat
exchanger 140.
[0053] The mixture from heat exchanger 140 is fed through line 145
to static mixer 160 where it is contacted with aqueous catalytic
composition from tank 150 fed via line 152, pump 155 and line 157.
Optionally, carbon dioxide is fed from reservoir 170 through line
175. The heat exchanger is optional and only used if necessary to
maintain stream 145 at approximately 65-110.degree. C.
[0054] The output stream 165 of the static mixer is fed to a
settling tank 180 where the mixture settles and forms distinct
layers. The solids layer 196 contains the particles from the
aqueous catalytic composition and any precipitates or other solid
materials e.g., soils, sediments, rock mixtures and sands.
Sulfur-based and metallic impurities present in the starting
materials also form solid. The aqueous layer 192, formed above the
solids layer 192 contains most water. Above the aqueous layer 192,
is the hydrocarbon layer 188 containing lower molecular weight
hydrocarbon products. Above the hydrocarbon layer 188, is the
gaseous layer 184. The gaseous layer 184 typically contains light
hydrocarbons that are not liquids at the operating temperature and
pressure in the settling tank 180 as well as any other volatiles
formed in the process.
[0055] The precipitated aqueous catalytic particles, which
collected at the bottom of the pressure tank in the experiments
described below did not become coated with carbon and based on
x-ray diffraction (XRD) and scanning electron microscope (SEM)
analysis, they may be reusable in the process.
EXAMPLE 1
[0056] The pilot scale examples were performed at a Steam Assisted
Gravity Drainage (SAGD) pilot facility in the Cold Lake area of
Alberta. The equipment used consisted of pumps, a pumper-mixer
truck, a pressure tank, controls, instruments, and connecting pipes
and hoses. The SAGD facility provided a produced water/oil emulsion
input stream with an average split of 20% oil to 80% water to the
pumper-mixer essentially configured as shown in FIG. 1 with the
water/oil emulsion stream replacing the high molecular weight
hydrocarbon source 110.
[0057] Between 9 m.sup.3 and 14 m.sup.3 of emulsion was processed
in each experimental batch. The treatment was done in a continuous
fashion. The Basic Solids and Water content (BS&W) of the
treated oil stream ran from 1% to 5%. The solids content was less
than 0.5%.
[0058] The control samples, marked Pilot Control 1, Laboratory
Controls A, B, C and D were prepared to generate comparative data.
Pilot Control 1 was performed in the pilot facility and the
Laboratory Controls were performed in the laboratory. Oil from the
same well and similar diluent hydrocarbons were used and mixed in
various proportions that matched and exceeded the diluent-to-oil
ratios used in the pilot facility. The oil used in Pilot Control 1
consisted of the oil alone with no added diluent hydrocarbon or
aqueous catalyst composition. To the Laboratory Controls, both
diluent hydrocarbon and aqueous catalyst composition were
added.
[0059] The aqueous catalytic composition was prepared by mixing the
following components in water in the percentages indicated:
TABLE-US-00003 TABLE 3 Precursor Component (Mix A) Wt % Portland
Cement 36 Volcanic Ash (Scoria) 55 TiO.sub.2 4 FeCl.sub.2 5
The weight percentages of the chemical compounds in Mix A, which
may vary from batch to batch by +/-15 wt %, are as follows:
TABLE-US-00004 TABLE 4 Precursor Compounds (Mix A) Wt % SiO.sub.2
24 Al.sub.2O.sub.3 6 Fe.sub.2O.sub.3 5 CaO 35 TiO.sub.2 4
FeCl.sub.2 16
[0060] Each of the samples marked as treated below used 2.5% by
weight of precursor components based on the net weight of oil in
the emulsion. In the case of the aqueous catalytic composition made
with aqueous ferrous chloride as a starting material, the percent
of ferrous chloride is based on the dry weight in the solution. All
experiments were run at approximately 75.degree. C. except
Experiment 6, which was operated at 25.degree. C. and Experiment 8,
which was operated at 100.degree. C.
[0061] Table 5 presents basic physical and chemical properties of
the untreated oil, control samples and treated samples.
TABLE-US-00005 TABLE 5 Summary of Physical and Chemical Parameters
Viscosity Vol. % Diluent Specific (cs) Added (Diluent Experiment
Gravity API.degree. at 7.degree. C. Density: 0.7247) Pilot Control
1 - 1.0040 9.4 1,600,000 0 field test, Lab Control A- Treated
0.9505 17.3 3,000 19.7 Lab Control B- Treated 0.931 20.4 745 26.9
LabControl C- Treated 0.9142 23.2 270 32.9 LabControl D - Treated
0.8942 26.7 100 40.9 Field Experiment 3 - 0.9151 23.0 109 19.6
Treated Field Experiment 8 - 0.8679 31.5 25 21.4 Treated Field
Experiment 5 - 0.9224 21.8 408 15.2 Treated Field Experiment 6 -
0.9054 24.7 283 4.6 2.sup.nd pass of Experiment 5
TABLE-US-00006 TABLE 6 Pilot Control 1 Experiment 3 Experiment 8
Untreated Oil Treated Oil Treated Oil Pour Point 15.degree. C. --
-51.degree. C. Bromine Number 3.00 2.2 2.2 Total Acid Number 1.29
0.91 0.75 Total Sulfur (vol. %) 4.56 2.98 3.41 Pipeline Compliance
N/A Passed Passed Test
[0062] Pilot Control 1 was a control experiment that did not
include any of the catalytic composition. This run only involved
water-oil emulsion and a relatively high level of diluent
hydrocarbon, namely, 30 parts by volume of diluent hydrocarbon was
added to 70 parts of oil (41.9% oil). From previous field
experience it was known that addition of more than 30% diluent
hydrocarbon is required to meet the viscosity requirements for
pipeline transport. Nine m.sup.3 of emulsion and diluent
hydrocarbon was processed in Pilot Control 1 with an emulsion
temperature ranging from 65.degree. C. to 80.degree. C.
[0063] Pilot Control 1 provided a basis for subsequently studying
the change in the composition of the gases in the top of the
pressure tank. This pressure tank was used as a collection vessel
for the treated or upgraded hydrocarbon fluid, water, gases, and
solid precipitate from the various experiments. It was evacuated
and cleaned after each run.
[0064] It was expected, based on the diluent hydrocarbon addition
of 23.6% by weight or 30% by volume of a blended diluent
hydrocarbon/oil barrel, that the release of C.sub.1 to C.sub.5
hydrocarbons as gas would be higher in Pilot Control 1 than
subsequent experiments. Experiment 3 used 15% by weight of a
blended oil/diluent hydrocarbon barrel and Experiment 8 had 16.4%
by weight of a blended barrel of oil/diluent hydrocarbon.
[0065] Experiment 3 provided an initial insight into the potential
level of effectiveness for cracking and hydrogenation by the
aqueous catalytic composition in a pilot scale environment. The
data in Table 5 and 6 show that significant and positive changes in
the density, API, viscosity, and decrease in sulfur content, were
achieved when compared with Pilot Control 1. In Experiment 3, 11.8
m.sup.3 of emulsion and diluent hydrocarbon were processed. The
temperature of the Experiment 3 emulsion was 65.degree. C. to
75.degree. C. just before the addition of the aqueous catalytic
composition and dropped after addition of the aqueous catalytic
composition. The temperature increased by about 5.degree. C. just
before the mixture entered the settling tank. The resulting lower
molecular weight hydrocarbon product had an API of about
23.degree..
[0066] This API value exceed the highest API value achieved at runs
performed at ambient temperature (16.degree. C. to 25.degree. C.)
with even two treatment passes with higher levels of diluent
hydrocarbon. While the earlier laboratory results were evidence of
a significant change, it was not as significant as the change that
occurred in Experiment 3 with an emulsion temperature of 65.degree.
C. to 75.degree. C. using only one treatment pass, 11.2% less
diluent hydrocarbon and 43% less precursor component composition.
The improved results can be explained from the increase in
temperature as well as a modification to the formula for the
aqueous catalytic composition.
[0067] Experiment 8 shows the outstanding result which can be
achieved by the practice of the invention. The product from
Experiment 8 had an API gravity of 31.5.degree. and a viscosity of
25 cs at 7.degree. C. 14.5 m.sup.3 of emulsion and diluent
hydrocarbon were processed. The product also had a lower molecular
weight with a lower bromine number (an indicator of the degree of
unsaturation of the hydrocarbons) as compared to the untreated oil.
The number dropped from 3 to 2. The total acid number dropped below
1.0 in Experiment 3 and 8. In Alberta, Canada, 1.0 is the threshold
point where pipelines implement financial penalties for
transporting the oil due to high acidity. Note also that the pour
point dropped from +15.degree. C. to -51.degree. C. on the oil from
Experiment 8. In this experiment, the emulsion temperature was
approximately 100.degree. C. just before the addition of the
aqueous catalytic composition. The temperature of the treated
emulsion stream leaving was approximately 75.degree. C.
[0068] Experiments 6 is the treatment of the product of Experiment
5 using again the process of the invention. Between 13 m.sup.3 and
14 m.sup.3 of emulsion and diluent hydrocarbon were processed in
Experiments 5 and 6. Experiment 5 was operated at about 65.degree.
C. to 75.degree. C. emulsion input temperature prior to the
addition of the aqueous catalytic composition. The emulsion
temperature prior to the addition of the aqueous catalytic
composition in Experiment 6 (the second pass) was about 18.degree.
C. to 25.degree. C. Experiment 6 used relatively low amounts of
diluent hydrocarbon, 3.4% by weight per barrel, and precursor
component composition at 1.64% by weight to the net weight of oil
in the emulsion. Based on laboratory measurements, the second pass
made (Experiment 6) made a significant improvement in both density
(0.9224 to 0.9254) and viscosity (API from 21.80 to 24.7.degree.)
This shows that further cracking and hydrogenation reaction can
take place by treating the product which has been already treated
using the process of the invention.
TABLE-US-00007 TABLE 7 Mass Boil-Off (%) by Temperature in
Simulated Distillation Analyses 0- 0- 0- 0- 200- 250- 350- 450-
125.degree. C. 150.degree. C. 200.degree. C. 350.degree. C.
250.degree. C. 350.degree. C. 450.degree. C. 525.degree. C. Control
10.2 11.2 12.8 26 2.4 10.8 14 10 A Exp. 3 17 19 22 35 3 10.2 12.8 9
Change 66.7 69.6 71.9 34.6 25.0 -5.6 -8.6 -10.0 (%) Control 22 24.2
26.8 39.5 3 D Exp. 8 23.6 25 27.2 39.5 2.6 9.7 11.5 8 Change 7.27
0.03 0.01 0.00 -0.13 (%) Control 10.2 11.2 12.8 26 2.4 10.8 14 10 A
Exp. 8 23.6 25 27.2 39.5 2.6 9.7 11.5 8 Change 131.4 123.2 112.5
51.9 8.3 -10.2 -17.9 -20.0 (%)
[0069] Control A has the same diluent hydrocarbon loading as for
Experiment 3. The distillation profile for Control D most closely
matches the distillation profile of Experiment 8, but it has a
diluent hydrocarbon loading 2.55 times higher than for Experiment
8.
[0070] From Table 7 in the 0-125.degree. C. range (Light Straight
Run Naphtha) 66.7% by mass more of the lighter end hydrocarbon
compounds have boiled off from Experiment 3 than from the Control A
sample. In Experiment 8, 131.4% more light ends have boiled off
than for the Control A sample. Experiment 8 has only 10% by mass
more added diluent hydrocarbons than the Control A sample.
[0071] In the 0-200.degree. C. range (Light and Heavy Straight Run
Naphtha), Experiment 3 generated 71.9% more light ends than the
Control A sample; Experiment 8 generated 112.5% more light
hydrocarbons than did the Control A sample.
TABLE-US-00008 TABLE 8 Residual Fraction (Boiling points higher
than 530.degree. C.) Residual Fraction % Change from Untreated case
Untreated Oil 0.67 Experiment 3 0.44 -34.6 Experiment 8 0.41 -5.5
Control A 0.50 20.8 Control B 0.47 -5.4 Control C 0.45 -4.9 Control
D 0.40 -10.9
[0072] In Table 8, with respect to the reduction in the residual
fraction (the compounds that boil above 530.degree. C.), there is a
reduction of 34.6% (14.5 gallons per barrel of crude oil) in the
treated oil from Experiment 3 compared to the untreated oil.
TABLE-US-00009 TABLE 9 Percent Changes for Table 4A % Change from
Control A to Experiment 3 = -12.4% % Change from Control A to
Experiment 8 = -17.2% % Change from Control B to Experiment 8 =
-12.5% % Change from Control C to Experiment 8 = -8.1%
[0073] The treated oil from Experiment 3 has 5.2 gallons per barrel
less residual than that from the Control A experiment. There is a
16 gallons per barrel reduction in the residuals in Experiment 8
compared to the untreated oil. The treated oil from Experiment 8 is
7.2 gallons per barrel lower in residuals than that from the
Control A experiment, and 5.3 gallons per barrel lower than that
from the Control B experiment. Treated oil from Experiment 8 is
even lower in residuals, 3.4 gallons per barrel, than that from the
Control C control experiment which had almost double the initial
loading of diluent hydrocarbon.
[0074] Table 10 compares the results of the SAPA (Saturates,
Aromatics, Polars, and Asphaltenes) separation analyses of four
samples of oil: the untreated oil, the outputs from Experiments 3
and 8, and Control A sample. The focus of the SAPA analysis is to
examine the saturate, aromatic, polar (resin), and asphaltene
fractions, as they exist above a 270.degree. C. boiling point.
[0075] The aqueous catalytic composition (upgrading) technology
applied in the pilot test changed an API 9.4.degree. oil with a
viscosity of 289,000 cs at 40.degree. C. into an API 31.5.degree.
oil with a 25 cs at 7.degree. C. These end-state changes are
average values over the whole barrel of incoming crude not just the
portion that boils below 350.degree. C. to 530.degree. C. which is
considered in some conventional upgrading processes.
TABLE-US-00010 TABLE 10 Saturates, Aromatics, Polars and
Asphaltenes (SAPA) Analyses-Changes in the Gas-Oil Range Mass %
>270.degree. C. Saturates Aromatics Polars Asphaltenes Loss of
Light Ends Untreated Oil 24.2% 35.0% 24.2% 15.2% 1.4% Treated Oil -
18.0% 24.7% 17.7% 11.6% 28.0% Run 8 Change -25.6% -29.7% -26.9%
-23.7% 1900.0% (Untreated to Experiment 8) Treated Oil - 17.6%
21.0% 24.6% 12.3% 24.6% Run 3 Change -27.3% -40.0% 1.7% -19.1%
1657.1% (Untreated to Exp 3) Control Sample 21.0% 25.6-% 26.5%
15.0% 11.9% A Change -13.2% -26.9% 9.5% -1.3% 750.0% (Untreated to
Control A) Change (Exp. 3 2.3% 17.6% -28.0% -5.7% 13.8% to Exp. 8)
Change (Control -16.2% -18.0% -7.2% -18.0% 106.70% A to Exp 3)
Change (Control -14.3% -3.5% -33.2% -22.7% 135.3% A to Exp 8) SAPA
measured in terms of sample mass percent of a barrel above a
boiling point of 270.degree. C. The five fractions of the SAPA test
represents 100% of the barrel of oil. This test starts at a boiling
point above 91% of the mass of the added diluent hydrocarbon.
[0076] This degree of change, along with the other factors listed
above, has a significant impact on the value of the oil. This
upgrading technology can be applied to the raw oil in a produced
emulsion from the well or bitumen extraction plant with no chemical
or other form of pre-treatment.
[0077] The compounds with boiling points below 270.degree. C. are
eliminated from analysis by the SAPA test and are listed as a fifth
fraction, "Loss of Light Ends". Insight into what constitutes the
"Loss of Light Ends" fraction is given from Table 7.
[0078] Table 10 shows a consistent reduction in the heavier, higher
boiling-point hydrocarbon compounds and the corresponding increase
in lower molecular weight and lower boiling-point compounds by
employing the process of the invention. Molecular and colloidal
hydrocarbon structures in the saturates, aromatics, polars
(resins), and asphaltene classes in the feed oil are broken down by
cracking and hydrogenation mechanisms and appear in the treated oil
as compounds that boil below 270.degree. C. These lighter and lower
boiling point compounds are moved into the fifth fraction of the
SAPA analysis, "Loss of Light Ends".
[0079] Comparing the properties of the treated oil from Experiment
8 with the untreated oil sample and the Control A sample, there is
a significant reduction in the higher boiling point saturates
(-25.6%), aromatics (-29.4%), polars (-26.9%), and asphaltene
(-23.7%) fractions and a significant increase in the "Loss of Light
Ends" fraction of 1900%. In comparing Experiment 8 with the Control
A sample there is a change of -14.3% in saturates, -3.5% in
aromatics, -33.2% in polars, and -22.7% in asphaltenes, and an
increase of 135.3% in the Loss of Light Ends.
[0080] Table 8 shows the distribution and changes of the
significant hydrocarbon compound structural fractions of the "Loss
of Light Ends" segment from Table 5, SAPA. Specifically, the area
of focus of the PNA test is in the 0.degree. C. to 275.degree. C.
boiling point range.
TABLE-US-00011 TABLE 11 Changes in Concentrations of Paraffins,
Naphthenes, and Aromatics (0 to 275.degree. C. Boiling Range)
Composition (% weight) Mono- Paraf- Naph- 1 2 Aro- aro- Alkyl-
Naphtha- Diaro- Naphtha- fins thenes Ring Ring matics matics
benzenes lenes matics lenes Control 56.70 32.60 26.40 6.20 10.70
10.10 8.50 1.60 0.70 0.70 A Exp 3 57.10 32.00 27.10 4.90 10.90
10.20 8.80 1.40 0.70 0.70 Exp 8 68.30 24.40 21.40 3.00 7.40 7.00
6.30 0.70 0.40 0.40 Changes in Comparison To Control A Sample Exp 3
0.7% -1.8% 2.7% -21.0% 1.9% 1.0% 3.5% -12.5% 0.0% 0.0% Exp 8 20.5%
-25.2% -18.9% -51.6% -30.8% -30.7% -25.9% -56.3% -42.9% -42.9%
Changes from Experiment 3 to Experiment 8 Change 19.6% -23.8%
-21.0% -38.8% -32.1% -31.4% -28.4% -50.0% -42.9% -42.9% Exp 3 to
8
[0081] The PNA tests show that there is a chemical break-up
(cracking and hydrogenation) of the heavier molecular compounds
into lighter hydrocarbon compounds. In support of this, Experiment
8 shows significant reductions in naphthene content (-25.2%) and
aromatic content (-30.8%) and an increase in the lower
molecular-weight paraffin content (+20.5%) compared to the Control
A sample.
[0082] The product from Experiment 3, as compared to the untreated
oil, has a decreased content of six metals, an increase content of
six other metals, and no change in the content of seven further
metals. Significant decreases also occurred in the amounts of
boron, molybdenum, silicon, sodium, and vanadium present in the
output from Experiment 3; there was a significant increase in the
amount of calcium present (90 ppm).
[0083] The treated oil from Experiment 8 also shows, in comparison
to the untreated oil, a decrease in the content of six metals, an
increase in the content of six other metals, and no change in the
content of seven metals. Significant decreases occur in the amounts
of boron, chromium, molybdenum, silicon, sodium, vanadium, and zinc
in the output from Experiment 8. There was a significant increase
in the calcium content (120 ppm) but this is not believe this
negatively affects the oil's value at the refinery.
TABLE-US-00012 TABLE 12 Analyses of Gases (in ppm) in Headspace of
Pressure Collection Tank Diluent Change Experi- HC Added from ment
Vol % H.sub.2 CO.sub.2 Control % C.sub.1 C.sub.3 iC.sub.4 nC.sub.4
nC.sub.5 C.sub.6 C.sub.7 Control 30 1100 41,600 843,400 9,800 6500
29,000 17,300 1200 100 Exp 1 (65-75.degree. C.) Exp. 3 19.6 1900
44,700 7.5 777,900 9,600 7900 39.500 40,500 6000 600
(65-75.degree.) Exp. 8 21.4 0 2,700 -93.5 961,300 600 200 800 4,300
3900 1200 (100.degree. C.) Exp. 5 15.2 0 2,900 -93.0 895,400 1,300
1000 6,000 32,400 12400 1700 (75.degree. C.) Exp. 6 4.6 100 6,200
-85.1 888,000 3,400 2600 14,200 25,400 8200 2000 (20.degree.
C.)
Since the boiling point of C.sub.6 is 69.degree. C. and of C.sub.7
is 98.degree. C. and the temperature of the liquids and gases in
the pressure tank were far below 69.degree. C., the concentrations
of C.sub.6 and C.sub.7 in the vapor phase is likely to be only a
small fraction of their concentrations in the liquid phase.
Similarly, the concentrations of these in the gas phase, as shown
in Table 11, are quite low; however, there is a substantial
concentration of gasoline range hydrocarbons in the liquid phase.
The PNA test data, Table 10, and the simulated distillation data
(not shown) further support an increase in light hydrocarbon liquid
concentrations.
[0084] There is a 93.5% drop in the concentration of CO.sub.2 in
the pressure tank headspace from the control experiment to
Experiment 8. It is of interest to compare the composition of gases
in particular experiments especially where the differences were
significant as compared to the control experiment. In Pilot Control
D, there is relatively high loading of diluent hydrocarbon. This
generates a disproportionately high level of light-end hydrocarbons
compared to the experiments where the products are treated in
accordance with the invention. Also, the diluent hydrocarbon
loading in the Control is near that necessary to reduce the
viscosity of the heavy oil to a degree that it can be transported
through a pipeline. The proportion of light molecular weight gases
generated in Control Experiment 1 is abnormally high because of the
relatively high diluent hydrocarbon addition compared in this case
to the other experiments. This presents a significant threshold for
the subsequent experiments to exceed in terms of showing real or
significant chemical changes occurring as opposed to experimental
measurement error or noise.
[0085] Control Experiment 1 involved 53% more diluent hydrocarbon
by volume than did Experiment 3 but Experiment 3 resulted in 42%
more hydrogen, about the same level of CO.sub.2, and approximately
the same level of light hydrocarbon concentrations C.sub.1, and
C.sub.3, as Experiment 1. But from C.sub.4 to C.sub.7. Experiment 3
had significant increases in compound concentrations over the
control experiment. There is a 36% increase in n-C.sub.4, a 95%
increase in i-C.sub.5, a 134% increase in n-C.sub.5, a 400%
increase C.sub.6, and a 500% increase in the C.sub.7
concentration.
[0086] The concentrations measured in the product from Experiment 3
do not follow the trends of the subsequent experiments. One
explanation for this is that the sample analyzed is not truly
representative of the output from this experiment. However, the
sample used to represent Experiment 3 gave good or consistent
measurements in all other tests.
[0087] The treated oil from Control Experiment 1 has 40.2% by
volume more diluent hydrocarbon than does that from Experiment 8
but the Experiment 8 oil has no detectable hydrogen, it shows a
major drop in CO.sub.2 concentration of 93.5%, and a significant
increase in C.sub.1 concentration of 14%. But from C.sub.3 to
C.sub.5 the Experiment 8 output has significant decreases in
compound concentrations compared to the output from the control.
There is a 93.8% decrease in C.sub.3 concentration, a 97.2%
decrease in n-C.sub.4, a 75% decrease in n-C.sub.5, an increase in
C.sub.6 of 225%, and an 1100% increase in the C.sub.7
concentration.
[0088] There are significant differences between the headspace gas
compound concentrations measured in the control experiment and the
corresponding data from Experiments 8, 5, and 6. This implies a
very active and positive effect of the aqueous catalytic
composition. The is significant differences in distillation
profiles between the treated samples from Experiment 3 and
Experiment 8 and those of the various Control Samples (A, B, C) The
differences are most pronounced with respect to Control samples A
and B, particularly in the 0-150.degree. C. range and the
0-250.degree. C. range.
EXAMPLE 2
[0089] To further demonstrate the invention, pilot testing was
performed in Lloydminster, Alberta, Canada. The oil from this
region differs in composition from that used in the data reported
above, i.e., from the SAGD Facility in Cold Lake.
[0090] The Lloydminster (Lloyd) pilot plant was designed on same
basis and process concepts that was used at the Blackrock Cold Lake
facility. Difference in the two facilities were that the Blackrock
facility had a smaller capacity operation, the water/oil emulsion
was already heated to 170.degree. C., coming out of ground from a
SAGD production operation, and at the Lloydminster plant the
water/oil/CO.sub.2 emulsion was heated in a line-heater before was
aqueous catalyst composition was blended into the emulsion stream
at 95.degree. C. to 115.degree. C. At the Lloydminster facility,
oil was trucked off and loaded into heated 1000 bbl storage tanks.
The storage tanks were heated to 85.degree. C. The approximate
percent composition of the components of the catalyst precursors
used it these experiments are as follows:
TABLE-US-00013 TABLE 13 Precursor Components Mix B (Wt %) Mix C (Wt
%) Portland Cement 20 26 Volcanic Ash (Scoria) 71 79 TiO2 4 4 FeCl2
4 5
The weight percentages of the chemical compounds in Mix, which may
vary from batch to batch by +/-15 wt %, are as follows:
TABLE-US-00014 TABLE 14 Precursor Compounds (Mix C) Wt % SiO.sub.2
39 Al.sub.2O.sub.3 12 Fe.sub.2O.sub.3 8 CaO 21 TiO.sub.2 5
FeCl.sub.2 5
[0091] The Lloydminster plant process system is a open system
beginning at the treater or horizontal separator. Accordingly, any
gases or vaporized light liquids with boiling points below the
maximum horizontal separator temperature of 110.degree. C.
vaporized out of the system either to the off gas/liquid collection
tank or to the atmosphere. These vapor losses definitely negatively
affected the upgrading result with respect to density and viscosity
of the treated oil. The "sales tanks," at the end of the process
stream, are also a point of vapor loss. The losses involve a range
of light and middle range boiling point hydrocarbon compounds.
[0092] Table 15 below shows and untreated Lloydminster oil and
three treated samples. The first two treated samples were treated
with different catalyst. Both with the addition of CO.sub.2.
Concentrate was added to Sample 7. The Sample 7B was prepared by
taking the treated product of Sample 7, and adding 15 g of the
condensate to 100 g of the Sample 7 product. Table 15 summarizes
the sample preparation and the results obtained:
TABLE-US-00015 TABLE 15 Density, Viscosities, and Total Acid
Numbers for Samples Viscosity Total Acid Density API 20.degree. C.
Number Untreated Lloyd Oil 0.9890 11.4 19,964 6.65 Mix C 1.8 wt % 2
scft/min 0.9499 17.5 824 CO.sub.2, No Condensate Added Sample 7,
2.3 wt % Mix B, 0.9556 16.5 1,449 2.45 4.5 scft/min CO.sub.2, 13 wt
% condensate Sample 7B, 13 wt % 0.8960 26.3 77 0.65 condensate
blended after initial treatment
The above data shows the substantive viscosity reduction achieved
with the first two treated samples. The comparison between samples
7 and 7B shows the efficacy of a two stage treatment with the
catalyst of the invention: there is substantial improvement in
density, API, viscosity and total acid number.
[0093] The Table 16 below is SAPA analysis of untreated oil and the
products of Samples 7 and 7B treated oils which boil above
260.degree. C. The data show how the latter compositions differ
from the untreated or raw oil. The saturate compounds increased 21%
in Sample 7 and 29.9% in Sample 7B. This increase likely came from
saturated aliphatic hydrocarbon fragments, probably cycloparaffins;
from the heavy gas/oil fraction or from fragments from the cleavage
of benzene rings from the aromatic fraction; or even from the
residual fraction.
[0094] Aromatic compounds decreased by 10.8% in Sample 7 and 16.6%
in Sample 7B. In order for there to be a decrease, the process of
the invention must cleave the benzene ring.
TABLE-US-00016 TABLE 16 SAPA Analysis of Samples 7 and 7B Compared
to the Untreated Lloyd Oil (270.degree. C. and Above) % Loss of
Sample Saturates Aromatics Polars Asphaltenes Light Ends Untreated
Oil 14.7 35.0 42.9 7.4 7.8% Sample 7 17.8 31.2 43.4 7.6 15.6%
Sample 7B 19.1 29.2 44.8 6.9 22% % Change from 21.0% -10.8% 1.1%
2.7% 100% Untreated to 7 % Change from 29.9% -16.6% 4.4% -6.8% 182%
Untreated to 7B % Change 7.3% -6.4% 3.2% -9.2% 41% 7 to 7B
EXAMPLE 3
[0095] This examples compares four treated samples. Treated Sample
38 was treated with 2.4% of the Mix A catalyst (based dry wt. % of
precursors to net weight of oil) at an emulsion temperature of
104.degree. C. Sample 47 was treated with 1.7 wt % Mix A catalyst
at an emulsion temperature of 104.degree. C. In the treatment of
both samples 38 and 47, 4.5 scft/min of CO.sub.2 was added to the
emulsion. The "B" samples comprised the product of the treated
Samples 47 and 38 mixed with 13% by weight of condensate. It will
be noted from Table 17 below that post-treatment addition of
condensate results in a dramatic difference in the end state
density and viscosities in Sample 47B and 38B as compared to
Samples 47 and 38.
TABLE-US-00017 TABLE 17 Density and Viscosity of Mix A Treated Oil
Samples 38, 38B, and 47, 47B Sample Density API Viscosity at 20 C.
38 0.9826 12.4 31,479 38B (Sample 38 plus 13 wt % 0.9217 21.9 239
condensate) 47 0.9819 12.5 17,948 47B (Sample 47 plus 13 wt %
0.9189 22.4 193 condensate)
[0096] Condensate can also be added initially in the upgrading
process as well as afterwards, if the chemical structure of the oil
demands it. Even with the addition of condensate before and after
treatment, the process of the invention uses considerably less
condensate than that normally added to the Lloydminster area oil to
make the viscosity acceptable for transport in intercontinental
pipelines. Condensate addition to the Lloydminster oil for the
purposes of pipeline transport can be in excess of 30%.
[0097] For Samples 38 and 47, data show a positive chemical change
in the SAPA analyses after a single treatment pass through the
plant. This pattern of change is similar to that shown for Sample
7. There is an increase in the saturates, a reduction in aromatics,
and an increase in polar compounds, asphaltenes, and "Loss of Light
Ends" fractions.
[0098] When condensate is added to the Samples 38 and 47, the
pattern again is the same as for Sample 7, except for the
asphaltenes fraction. There is an increase in the saturates, a
reduction in aromatics, and increase in the "Loss of Light Ends."
In Samples 38B and 47B there is no change in the asphaltenes, while
Sample 7B there is a 6.8% reduction. The post addition of
condensate shows there is a disproportionate change in density and
viscosity compared to what would be expected fro simple dilution.
Most importantly, the samples "B" were stabilized and did not
separate by density. The added condensate shows a significant
solvent effect or bonding to stabilize the hydrocarbon complexes
that make up the oil so that density and viscosity is homogenous
throughout the volume of liquid. The condensate has a catalysis
like effect that is effective after the Lloydminster oil has been
treated by the process of the invention.
[0099] The PNA analysis of Samples 47, 47B, and 38B follow the
pattern and direction of change seen in the PNA tests for Samples 7
and 7B. The PNA test covers the 0.degree. C. to 270.degree. C. With
regard to the PNA data for Samples 38 and 47, the data show that
aromatic compounds in the residual fractions go down significantly
and that paraffins and naphthenes increase significantly.
EXAMPLE 4
[0100] This Example shows that by the use of the aqueous catalyst
system of the invention, CO.sub.2 converts to organic compounds. To
show this, 5.75 mols per hour of CO.sub.2 was injected into the
emulsion flow system. It was observed that, in the 90 barrels of
water recovered, there were 700 ppm in water phase. The equates to
313 mols of methanol. In an initial investigation, a mixture of
water and oil containing a precipitate of a catalyst of the
invention was collected from the separator of the pilot plant after
the plant was shut down. The water phase was analyzed and found to
contain 2,430 ppm of methanol and 5,275 ppm of isopropyl alcohol.
It is believed, that in the practice of the invention for upgrading
oil, such low boiling material would have the added effect of
further reducing the viscosity of the upgraded oil.
[0101] Table 12 sets forth above shows an analysis of the product
gases in the headspace of the pressure collection tank where the
invention was practiced with the addition of carbon dioxide. In the
control runs with just oil and condensate, 42,000 ppm of CO.sub.2
was found. Where the aqueous catalyst of the invention was added to
the oil and condensate, there was a significant drop in CO.sub.2
concentration, an increase in methane and C.sub.6 and above
hydrocarbons, and a reduction in the C.sub.2, C.sub.3 and C.sub.4
hydrocarbons. Based on these observations, it was concluded that
methane and alcohols having two to four carbon atoms was formed. Of
particular interest in connection with Table 9 is the marked
reduction of carbon dioxide in Experiments 5 and 8.
[0102] All references, patents and patent applications cited and
discussed in this specification are incorporated herein by
reference in their entirety and to the same extent as if each was
individually incorporated by reference.
* * * * *